Steam generator



Maid. s, 1928. l

v H. A. NICHQLSON STEAM GENERATOR med .nine 24. 1919 4 Sheets-Sheet l l.@@@QQQQQQ Q @@@QQQQQQVQQ @@@QQQQ March 6, 1928.

1,661,545 H. A. NICHOLSON f Y STEAM GENERATOR Filed June 24, 1919 4Sheets-Sheet 2 March s, 1928. 1,661,545

H. A. NlcHoLsoN STEAM GENERATOR Filed June 24. 1919 sheets-spes: 3

INVENTOR H. A. NICHOLSON Mmh 6, 192s. y

s'rim GENERATOR Filed June 24. 1919 4 sheets-sheet 4 NN mh PatentedMair. GQ-19218.v

fiiinmisttY A. CRAIG;` or AUCkLANn NEWZEALANDQ f STEAMr Gnnn'RATonApgiivcanon ieaxun'e 24,1519.4 semina. 730639.00. i l

This invention relatesto stea1n-generatof's,`

` especiallyfthoseofthetypedisclosedin my pending application, SerialNo.284,657;, filed j March 24,1919,in which .Water is forced-t0 "5.flowinfa single Vdirection jthrouglia systemv j vor pipingl whichissubjected to thehea-t-.of

a urnacejlwherebythe fluidV is grtuzlually heatedfand-given a Ahighpressure asfitadf n avances" to the deliveryglend of. thegenerator.;

One of the Amain objects oftheinyention"l is\to pro`v1de-aninexpensiveand 'elhcient l-generator oi a vsimple typ'eyandto this end is the Waterispu'inped directly throughigaref l f sexjgve-.drumtoy a systeinuo'trtubing compris# ing 4nuin'e'rousfcoils;arranged preferablyoneaboveanotherinthe flame or heating chainf' `l ber ot' l the generator ;Ai Vthe `fluid -rdescending le0 coil lryfleoiliroinfgthe topgtothefbottoinaoi' tional. heat to any 'residuuin of fluid` therein i ,ri-uns."and thence down to thebottoni of `4o the coilsysteiiusofthatgenerationlofsteani may-be maintained `temporarily AWhile the` whichsupplies the ,'generator', and they may bejacketedby a refractoryheat-conducting ,land radiating material of the kind set vforth "in saidapplicationg-Ineans beine` enclosedtube, to ayOidunduecOOIing ofthegjacket bythe 'fluidinthe tube;` it being. intended that the jackets"should :inaintain an `incandescent condition, so' asto Ylengthen.

the system, and beingjthen TledtO a steain- Y driuniv Boththelfsteanifd'uin andfiefserve-`4 waterfdruu'i areplacedn the upper part"iVoflthe general'org;` and the Waterfinltlle .Wa-

ntei-drxun is hence heated,moderately .beforei it flows into thef coilsfof tubing', while thefsteamdrum is heated .orsupplying Laddi-l in theform o:t'. water Aat the `temperature and Ypressure of tliesteja'm inthe drum. -V

Means yis provided for `drawing upon the reserye` Water. in theWater-.drurniin case the u `feede'pui'up'. is-:te'inporarily stopped,:on in:

case any obstacle `bepresent inthe system the Water-drumand steam-drumbeing, diu rec'tly `connectilvileg,"` and i other. provision lbern)iiiadegfor causing the :heated ,fluidi to irculate `np wardly\ inl thecoil' systenr,tothe4 '..lhe tubes .in the coilsyyiihich together,may`thin-inn single .line ofgpiping, are preterably ot' the sanieVdiarneterrasV the Water-mainV A provided for, separating 'each jacket;agtrife -froni `its Y for ijprolong, the life ofthe iiannesfwhch,v

lapthe jackets. f

` YLfit' is desired tol secure a niorelrapici circulationof the Waterinthe generator when the pumpV is closed down, there )nayV "be used fanauxiliary circulator .or pump* "which ina-y be driven byfany` suitablesource;

otpower tolset the-Water actively circulating-throughout thefgenerator,thus* avoiding liability of ury tothe generator `by lreason l oi theyst:i;:,natio1i-ofl the lfluid at any point therein.

Q Otllel' features-and adyantages vvwill here;` I* :matterappear..` I Yln the accompanyingdrawings, i

Figurel is a sectionalY side elevation" of one `torni otgenerator'elnbodying the presi entfimprovements.f f

Figure 2 is a diagraii'itoillustrate the How# i S of the l lWaterthrough lthef generator. f f Figure A3 is a c sectional side4 elevation,"illusf with one another.

Figurel: is `anenlarged sectionalfdiagrani of adjoini'ng tubeswwiththeir frefractory jackets, and illustrating a supportin' blockoi'gsimilar material placed betweent e tube jackets."

i. Figure is aplan yof the lgenerartor'.V A

vFigure `G is a` sectional planfof one of-.the

"ss i horizontal coilsl 'mounted in the `Haine-charnhotfgases flowingupy through the generator to a stack 141; the top of the generator com-`.prisingfa dome 15rv Within which said drinn is karrangedin Vsuchamanner that thees?H raping gases circulate freely aroundthel, i

y In the upper-part of said druin 12,1at they other end from theinletl16,"-is anoutlet 17.; connected `by an elbow` 18 and a short ver-Iv tical pipe .19? to another elbo-WQQO .and a l,

horizontal Lpipe12'1 to the receiving end- 22 u. u '1.6 tratlng theconnect-ion ot the horizontal coils` i ia of a system ot recumbent coils23 arranged within a, combustionchamber 24, the latter comprising frontand rear walls 25, 26, and side Walls 2i', 28. Y

The coils 23 are so arranged in tiers or one above another that thewater flows entirely through all the tubes 29 in one coil or tier, andthen down through a duct 30 to the receiving end of the next. coil ortier, and then through all the tubes 29 in the second tier to thedelivery end thereof, and thence down through a duct or union 30 to thereceiving end of the third tier, and S0 on to the bottom ot' the systemot tubing coils. At Figure l. the tubes 2t) in this system or gridwork,which may be of the same diameter as thewater-mains, are seen incrosssection,` while Figure 6 is a sectional plan, showing a single tieror coil of the tubes, whiehare joined at alternate ends by U- passages3l `formed in headersk 32, making a. zigzag coil. Tlu` gridwork may beconsidered as comprising a series o t horizontal coils arranged oneunder another, and each connected to the next below it, to form a singlemain through which the fluid is `forced to ad unice always in onedirection by means of the torce-pumps, from top to bottom of thellame-chamber; and each coil ma comprisea row of tubes connected attheir ends in zigzag arrangement. The headers may have clean-outopenings closed by screwplugs A This flame-chaniber surmounts a fire-hox34, containing grates 35, and an ash-pit 36. The usual tire-door is seenat 37 and ashdoor at 38.

It will be seen that the fluid receives its final heating in passingthrough the lowermost coil 2S which is immediately over the fire-boxaandhence at the moment ot delivery trom the system the fluid is subjectedto the greatest heat; at this time its heat and pressureiare very high,say 350 pounds or, more to the square inch.

From the delivery end 39 of the lowermost coil, the Huid rises in a pipe4G to the top of the generator. and by means ot an elbow41 is led intothe lower portion ot a stea1n-drum 42, the inlet to the drum beingpreferably in the form ol a long horizontal pipe 43 extending nearly tothe opposite end of the drum (Figure 3), and having in its top smallperlorations 44 through which the overheated luid flows in the form of"steam to fill the drum; said pertorations serving to e choke back thehighly-heated pent-up fluid which is being forced to advance by thepumps, and preferably being ot such small dimensions that the pressureof the steam in the drum lmay be less than the pressure ot fluid risingto the drum in the pipe 40. It will be seen that provision is made torconverting pent-up, high-pressure, highlyheated fluid into steam,consisting of aseries or multiplicity of small outlets 44, each ol'which, because of its fineness, causes the fluid to be retained in theconverter pipe 43 at higher pressure than the steam in the service drum42, so that fluid may escape 'from the orifices in the form ot steam.Advantage is taken ol' the tact that cach orifice may be made smallenough to perform this function, and cri-operation may be secured ot amultiplicity oi orifices. This feature is not, however, limited to aconverter pipe arranged within the steam-drum, as the con verterorifices may be otherwise provided. Thus highly-heated fluid may remainpent up at high pressure in the fluid-piping system and maybe issued assteam without the use ol a movable valve. The steam-drum 42 is a servicedrum, from which steam is rapidly withdrawn, whereby the tendency is tolower the pressure in the drum relatively to the pressure in the. pipingthat supplies the drum; and the minuteness of the perforations in theconverter pipe enables the pipe to hold back the tluid at a pressureabove that of the steam in said drum; certain of the water content ofthe fluid being expanded or converted into steam as it passes from thehigh-pressure pipe 43 into the lower pressure drum 42. 1t is notessential that all ot the fluid enter the steam-drum in the form olsteam. Such as enters in the torni of water is subject to subsequent:heating from the heat ol the hot gases rising from the flame-chamber andcirculating around the steam-drum, whereby the water in the drum,havingr the heat and pressure of the steam, may be converted into theform ot steam as the pressure decreases due to the escape of the steamfrom the scrvicepipe.

The drum is supplied with a delivery or service-pipe 45, rising from thetop thereof and provided with a stop-valve 46. In case it becomesnecessary to stop the operation ot the pumps, or it, for any reason, theflow of fluid to the steam-drinn should be obstructed or stopped, avalve 47 may be opened in a by-pass 4S between the drums. so thatl acirculation of fluid may be main: t-ained in the tube system 23imlependently ot the pumps 10.

When the valve 47 is open, the direction of the fluid flow will bereversed, that is, the fluid will flow up in the gridwork and be delivercd through the pipes 2l. 19 to the waterdrum 12, which may communiy'ate through the by-pass 4S to the steam-drum. from whence the coolerportion of the fluid mav descend through the diagonal pipe 4() to thebottom coil in the system. Thus the generator is converted into acirculatory svstem, in which circulation will be maintained temporarilyuntil the obstacle is removed and the pumps started into action again.It will also be understood that this reverse circulation of fluid may berelied upon when an excessive proportion of Combustible gases f Thesewarming up the generator.- tothe point of steam productiomand thatthereupon theL valve 47 ini-the `hy-pass 48 maybe closed, and the pumpsstartedinto action, to cause steam` to be delivered to thesteam-drum42,as already explained. i i .1 i

Another method of securing a temporary circulation of the Waterthroughthe systemy independently of the force-pumps is alsov water-drum 12. From this drum steam may pass over through'aii ripper bypass 52 (containing a valve 53`Whicli` may now be open), Valve" into the top of thesteaiii-drum 42. 50 at top of pipe 40 may be closed, to cut `it oli'from the steanvdruin42. water may flow down through pipe 19into theuppermost ofthe g'ridsect'ions or coils, and thence down thegrid -to.the bottom thereof, and from thence it may be draivnup by theipumpthrough the diagonal pi pe` 40 to `the water-drum12,.'tlius` keeping' upthe circulation, `steam `passing oveivthroughV theopen .by-pass 52 `tothe steamidrum 42.

This pump serviceable tofwarni up the water quickly. 1

The tubes forming vthe coilsor sections are joined at alternate endsbythe U-shaped connections 31 termed in the horizontal headers 32, whicharearrangedone above K' another at the, sides or'ends ofthe flamechamber. In Figure-3 are "also shown cleanout openings closed bytheplugs 33. l At Figure l, the 'tubesare all shown as encased in jackets56 ofrefractory heat-con!` ducting material of the kind disclosed in 'myG57, 'filed March 24, 1919.AsV set orthin said application, thesejackets` become yincandescent and prolong thel life of the flame,

which would otl'ierwise vbe` prematurely cooled, thus shorteningcombustioinfso that would escape from the generator. jackets may becylindrical, and areppreferably oversize, and may be vprovided withinternal ribs or studs 57 placed at suitable intervals. so as to keepthejaclietsslightly separated from the tubes, for the purpose set forthin said application, whereby the heating ofthe tubes by the jackets iseffective through radiation, and ivhereby the pipes may have little orno tendency to cool the jackets, which it is desired to maintain in anincandescent condition. f i

At Figure 4 is shown a method of supporting the jackets by means ofblocks 58 The cooler 1 ofrefractory material, having concavesidesl and.fitting between 4adjacent jackets 56.

These. blocks or supports maybe placed either between laterally7adjacent tubes or Vbetween tubes arranged one above another, 'or bothmethods may be-used.

The opening 59 in the top or bridgeabove Y "the fire-box for the escapeof the flames -is seen at Figure 3. Amongthe tube coils maybe placedbaffle-plates 60 extending .j alternately from the back and front'of'thefiume-chamber, so that the flames mustjpursue a zigzag "course in risingto-the top of the generator. It will be` seen that the tubes are placedrather closely together side by side, so that theliamescannot readilycourse' I upwardly, `while the tube coils are separated coiiisiderablyone f above another, to give` ample 'room for lthe fiames, so thatcombustion may proceed slowly, and so that the life of the flames may beprolonged, and the tubes-iii the upper partof the. combustion'-chan'iber may be causedto dol a propershareA of theheatingof the fluid,so thatan undue proportion of the work of heatingthe Water will notlfall upon the tubes closest to the Variations may be `resorted to Withinthe scope of" the invention, and portions ofA the in'iprovements may beused Without others.

`Having thus describedV my invention, l"

claim: y

l. In a steam generator, thecombination oit a system of tubing and adrum connected therewith, a pump for forcingI fiuid only Vlowpressureservicesteanidrum, anda converter connected to the delivery'endof the "system of tubing and having a-portion eX- teiiding within theVsteam drinn, saidvconrverter having Within said drinn means for n"converting the high pressure iliid into lo\v said pending application,Serial! No. 284,'

pressure steam comprising numerousvsmall perl'orations opening into lthedrum, said pertoratious of such small dimension that vthe pressure ofthe fluid in the converter is maintained at a substantially higherpoint" than the pressure of steam in. the service drum, anduljiperandlower pipes for connecting the drums, said pipes havingvalvestherein `Which when open permit circulation of the fluid throughthedrums and tub-V ing. Y

2. In a steam generator, the combination nicating with the inlet end ofsaid tubing,v a

pump communicating-with said Water drum Vof a system of tubing, aivaterdrum commu-l l converting the highly heated pent up fluid into lowpressure steam, comprising a converter from which open numerousrelatively small outlets which choke back the pent up fluid and throughwhich fluid escapes into low pressure steam whereby the pressure offluid in thefluid tubes is kept at a higher point than the pressure ofsteam in the service steam drum, and means between the steam drum andwater drum to permit circulation of the fluid around and around throughthe system.

3. A steam-generator comprising a combustion or flame-chamber filledwith a .system of coils of tubing, said coils arranged one above anotherand connected in series to form a single fluid-course, hydraulic meansfor forcing fluid to advance in one direction from one end to the otherof' the system, a reserve-water-drum included between said forcing meansand said system ol coils, a steam-drum to which the delivery end oltsaid system of coils ,is connected, a by-pass being provided between.said drums, and a valve normally closing saidy by-pass, but when openedpermitting circulation of' fluid in the opposite direction through thetube system and drums, a heating chamber being provided in which saidsteam-drum is mounted.

4. A steam-generator comprising a system of continuous tubing, afeed-pump for forcing fluid to advance in a single direction through thetubing, means for heating the fluid to high pressure and temperature asthe fluid advances through the system, asteamdrum at the delivery end ofthe tubing system, means for temporarily converting the generator into acirculatory system, and an auxiliary pump connected to the system tocause the fluid to circulate therein at the cessation of the ope ationof the feed-pump, a heating chamber being provided in which saidsteam-drum is mounted.

5. A steam-generator comprising a system of'continuous tubing, afeed-pun'ip for forcing fluid to advance in a single direction throughthe tubing, means for heating the fluid to high pressure andten'iperature as the fluid advances through the system, a steamdrum atthe delivery end of the tubing system, means for temporarily convertingthe generator into a circulatory systen'i, an auxiliary pump, and meansfor operating said auxiliary pump, said auxiliary pump connected to drawfluid from one part of said tubular system, to deliver it to anotherpart thereof, whereby circulation may be maintained while the feed-pumpis ineffective, or while the generator is being warmed up,

a heating chamber being provided in which said steam-drum is mounted.

6. A steamegenerator comprising a system of continuous tubing, afeed-pump for forcing fluid to advance in a single direction through thetubing, means for heating the fluid to high pressure and temperature asthe fluid advances through the system, a steamdrum at the delivery endof the tubing system, means for temporarily converting the generatorinto a circulatory system, an auxiliary pump, means for operating saidauxiliary pump, said auxiliary pump connected to draw fluid from onepart of said tubular system, to deliver it to another part thereof,whereby circulation may be maintained while the feed-pump isineffective, or while the generator is being warmed up, and means toconnect and disconnect parts ofthe generating system from one another,so that repeated circulation of fluid may be secured by said auxiliarypump at will, a heating chamber being provided in which said steam-drumis mounted.

7. A steam-generator comprising a system of tubing, a feed-pump forforcing fluid to advance in a single direction through the tubing, meansfor heating the fluid to high pressui'e and temperature as the fluidadvances through the system, a steam-drum at the delivery end of thetubing system, a reserve water-drum for said system of tubing. anauxiliary pump, means for operating said auxiliary pump, said auxiliarypump connected to draw fluid from one part of said tubular system, todeliver it to another part thereof, whereby circulation may bemaintained while the feed-pump is ineffective, or while the generator isbeing warmed up, a by-pass connecting said stean'i-drum and said reservewater-drum, and a valve toclose said by-pass, a heating chamber beingprovided in which said steam-drum is mounted.

8. A steam generator comprising a combustion or flame chamber, steam andwater drums in the upper portion of the chamber, coils connected inseries and extending from the water drum downwardly in the chamberthence through a pipe upwardly to the steam drum, means for forcingfluid through the water drum and the coils into the steam drum in asingle direction of flow, and a plurality of pipes having valves`therein t'or connecting the upper and lower portions of said drums, saidpipes serving to allow circulation in the system when the valves areopen.

HENRY A. NICHOLSON.

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